JPH09151214A - Polypropylene molding and preparation of its base resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a crystalline polypropylene molding having higher heat resistance (HDT; deg.C) than expected from its m.p. (Tm; deg.C), and its base crystalline polypropylene. SOLUTION: Polypropylene molded item satisfying the following relationship between heat deflection temp (HDT; deg.C) and m.p. (Tm; deg.C), 5.7<=1.18×(Tm)-(HDT)<=6.9 is obtd. by molding the following crystalline polypropylene. The crystalline polypropylene is obtd. by polymerizing propylene itself or by copolymerizing propylene and a 2-12C α-olefin except propylene with a metallocene, selected from hafnocene, zirconocene or titanocene and aluminoxanes as catalysts.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polypropylene molded article. Specifically, it has a high melting point and has a much higher heat resistance (H
The present invention relates to a polypropylene molded product exhibiting DT) and a method for producing a specific crystalline polypropylene which is a raw material of the molded product.

[0002]

2. Description of the Related Art Crystalline polypropylene typified by isotactic polypropylene produced using a conventional Ziegler-Natta catalyst is excellent in mechanical properties and chemical resistance and is extremely useful in balance with economic efficiency. It is widely used in each molding field in consideration of the point, and a propylene crystalline homopolymer and a propylene-ethylene crystalline copolymer obtained by copolymerizing propylene and ethylene are also compared with the propylene homopolymer. Therefore, it is widely used in each molded article field by taking advantage of the property that it has both low crystallinity and glass transition point.

However, since usual crystalline polypropylene is subject to restrictions on its use due to the limit of its properties, improvement of the performance of crystalline polypropylene is desired for its solution. For example, in the field of injection molding, a method of increasing the comonomer unit content in the propylene copolymer to lower the melting point is adopted from the viewpoint of improving the transparency and improving the productivity by lowering the molding temperature.

However, in the above-mentioned conventional method, the heat resistance for compensating for the situation that the heat resistance of the obtained polypropylene molded article is lost as a result of increasing the comonomer component content in the propylene copolymer. There is a strong demand for measures to improve

On the other hand, in recent years, it has been known that propylene is polymerized by using a catalyst which is a combination of metallocene and aluminoxane different from the conventional catalyst system, and stereoregular polypropylene having a narrow molecular weight distribution can be obtained. Has become.

For example, a highly stereoregular polypropylene having a narrow molecular weight distribution has been obtained by polymerizing propylene using a catalyst composed of a silicon-bridged metallocene having a specific structure and an aluminoxane [Japanese Patent Laid-Open No. Hei 3 (1999) -311].
-12406, JP-A-3-12407, and
CHEMISTRY LETTERS, pp.1853-1856 (1989)].

The crystalline polypropylene obtained by this method has a narrow melting point and a high stereoregularity, so that it has a high melting point as compared with crystalline polypropylene obtained from conventional metallocene catalysts, and a highly rigid resin. However, the disclosure of the specific technique for the molded article is not found in the above-mentioned prior art documents. Moreover, according to the additional tests by the present inventors, a mold having desired properties has not been obtained from this resin.

[0008]

As described above, there remains a problem that the molded article molded from the crystalline polypropylene obtained by the known method has poor heat resistance.

The present inventors have conducted earnest research on the development of a polypropylene molded product that solves the above problems associated with known techniques. As a result, in the case of using a specific polypropylene obtained by using a specific metallocene catalyst as a molded article, it is difficult to reach even by modification by lowering the resin melting point by copolymerization with other comonomer. The inventors have found that a molded product having high heat resistance can be obtained, and have reached the present invention.

[0010]

According to the present invention, the intended effect of the present invention can be achieved by the technique having the following respective constitutional requirements: (1) A crystalline polypropylene molded article, Is formed from crystalline polypropylene having an α-olefin component content (Cm) of 0 to 15 mol% excluding propylene having 2 to 12 carbon atoms, and the deflection temperature under load (HDT; HDT;
And a melting point (Tm; ° C) of the molded product are represented by the following formula: 57 ≤ 1.18 x (Tm)-(HDT) ≤ 69 A polypropylene molded product characterized by the following: Is provided [where the deflection temperature under load (HDT) is
And 45.1MPa (= N / mm according to JIS K7207)
² ) Deflection temperature under bending stress]. (2) Deformation temperature under load (HDT; ° C) of the molded product and melting point (Tm; ° C) of the molded product are represented by the following formula: 58≤1.18 x (Tm)-(HDT) ≤68.5 2. The polypropylene molded article according to item 1 above, which satisfies the following condition. (3) Relationship between the deflection temperature under load (HDT; ° C) of the molded product and the melting point (Tm; ° C) of the molded product represented by the following formula: 58.5 ≤ 1.18 x (Tm)-(HDT) ≤ 68 The above item 1 or 2 characterized in that
The polypropylene molded product described in.

According to the present invention, there is also provided a method for producing a crystalline polypropylene suitable for a polypropylene molded article, which is a method for producing a polypropylene molded article satisfying the following relational expression: (4) Polypropylene In a method for producing a crystalline polypropylene suitable for a molded article, propylene is homopolymerized using a catalyst formed from the following compounds (A) and (B), or α excluding propylene and propylene having 2 to 12 carbon atoms is used. -A crystalline polypropylene having an α-olefin component content (Cm) of 0 to 15 mol% copolymerized with an olefin, the deflection temperature under load (HDT; ° C) of the molded article and the melting point of the molded article ( Tm; ° C.) represented by the following formula: 57 ≦ 1.18 × (Tm) − (HDT) ≦ 69 Method of producing polypropylene satisfying the following formula: Compound (A): π electron A transition metal compound having at least one role ligand, a compound (B): an aluminoxane (B1), an ionic compound (B2) which reacts with the transition metal compound (A) to form an ionic complex, and a Lewis acid ( One or more compounds selected from B3). (5) The catalyst according to claim 4, wherein the compound (A) is a transition metal compound having at least one π-electron conjugated ligand and the content of its chiral form is 80 mol% or more (transition metal standard). A method for producing the crystalline polypropylene described. (6) Compound (A) and compound (B) as a catalyst
A propylene homopolymerized in the presence of a product formed by combining an organoaluminium compound as (C), or propylene and an α-olefin having 2 to 12 carbons other than propylene are copolymerized. 5. The method for producing crystalline polypropylene according to 5 or 6. (7) The compound (A) has the general formula Q- (C ₅ H _4-m R ¹ _m ) -MXY-
Item 4 which is a metallocene represented by (C ₅ H _4-n R ² _n ).
The production method according to any one of 1 to 6: [wherein (C ₅ H _4-m R
¹ _m ) and (C ₅ H _4-n R ² _n ) represent a substituted cyclopentadienyl group, m and n are numbers from 1 to 3, and R ¹ and R ² may be the same or different. , And each one or more carbon atoms which may be substituted with a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group or two carbon atoms on the cyclopentadienyl ring, which may be substituted with a hydrocarbon. It represents a hydrocarbon group forming a hydrogen ring, and Q is a divalent group capable of cross-linking (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n ). Is a hydrocarbon group, an unsubstituted silylene group or a hydrocarbon-substituted silylene group, M represents a transition metal selected from the group consisting of hafnium, zirconium and titanium, and X and Y may be the same or different. , And each represents one or more selected from hydrogen, halogen and hydrocarbon groups] (8) Item 4 to 7 above, wherein the transition metal element forming the metallocene is hafnium or hafnium having a purity of 80% by weight or more.
The manufacturing method according to any one of 1.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the metallocene used in the present invention is referred to as a "specific metallocene", and the metallocene catalyst used in the present invention is referred to as a "specific metallocene catalyst" in distinction from general metallocenes. Sometimes.

The crystalline polypropylene which is a molding material in the present invention is a propylene homopolymer or an α-olefin having 2 to 12 carbon atoms excluding propylene and propylene, for example, ethylene, propylene, 1-butene, 1-pentene. , 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, and the like, which is a copolymer with 0 to 15 mol% of α-olefin polymerization component, preferably 0 0.01 to 12 mol%, particularly preferably 0.05 to 1
It means an isotactic propylene (co) polymer contained in the range of 0 mol%.

The heat resistance of the polypropylene molded article which is an essential requirement of the polypropylene molded article of the present invention, that is, the deflection temperature under load (HDT) is the deflection temperature under load measured under bending stress of 45.1 MPa according to JIS K7207 ( HDT; ° C). The measurement results show that the heat resistance of the molded product increases as the deflection temperature under load increases.

The melting point (Tm; ° C) of the molded article, which is an essential requirement of the polypropylene molded article of the present invention, is the melting point of the molded article measured by the following measuring apparatus according to the following conditions and procedures: Measuring device: Differential scanning calorimeter [Brand name: DSC7 type (manufactured by Perkin-Elmer Co.)] ◆ Sample preparation: 230 ° C under conditions of temperature rising rate of 30 ° C / min from room temperature of a sample scraped from polypropylene molded product
After the temperature is raised to 10 minutes, the temperature is kept at the same temperature for 10 minutes, and then the temperature decrease rate is 20.
The temperature is lowered to −20 ° C. at a rate of 10 ° C./min, and the temperature is maintained for 10 min. ◆ Measurement condition: The sample prepared by the above sample preparation is introduced into the above measuring device, and the maximum endothermic amount (area) observed when the sample resin is melted under the condition of the temperature rising rate of 20 ° C / min.
The melting point (Tm; ° C) is defined as the temperature at which the peak showing "" is located.

The deflection temperature under load (HDT; ° C) of the molded product and the melting point (Tm, unit: ° C) of the molded product, which are essential requirements for the polypropylene molded product of the present invention, are expressed by the following equation.
(1) 57 ≦ 1.18 × (Tm) − (HDT) ≦ 69 ... (1), and preferably expressed by the following equation (2) 58 ≦ 1.18 × ( Tm)-(HDT) ≤68 ... (2), and more preferably, the relationship represented by the following equation (3) 58.5≤1.18 × (Tm)-(HDT) ≤ 67.5 ...
The relationship satisfies (3).

The object of the present invention is not achieved at a low deflection temperature under load which is considerably lower than the lower limit of the above relation (1).
Further, even at a high deflection temperature under load far exceeding the upper limit of the above relationship (1), the intended effect of the present invention is not found, and both are out of the technical scope of the present invention.

As the polypropylene molded article, any molded article is within the scope of the present invention as long as it satisfies the above-mentioned essential requirements of the present invention. Among them, the molded article of the present invention has a high deflection temperature under load. High heat resistance (HDT: heat distortion temperature) shows the maximum usefulness in the field of molded products, especially injection molded (injection molded) and extrusion molded (mostly blow molded) products, especially injection molded. Goods is a preferred field.

Here, the "injection molding" method is not limited to a mere injection molding method, and a combination of it with another molding method, for example,
It also includes an "injection blow molding" (injection blow molding) method. The crystalline polypropylene produced by the production method (mainly the polymerization method) of the present invention is suitable as a material resin for this injection blow molding method. The reason is that the material resin obtained by the production method of the present invention has a crystalline melting point (Tm)
Much higher heat resistance than expected from heat distortion temperature
Required to indicate (HDT).

The crystalline polypropylene used in the production of the polypropylene molded article of the present invention is produced using a specific metallocene catalyst, and the production method thereof will be described here.

The specific metallocene catalyst used in the production of crystalline polypropylene used as a material for the polypropylene molded article of the present invention is the following compound (A), compound
A catalyst comprising (B) and a compound (C) optionally combined. Compound (A): Transition metal compound having at least one π-electron conjugated ligand Compound (B): Aluminoxane (B1), an ionic compound that reacts with the transition metal compound (A) to form an ionic complex ( B2) and one or more compounds selected from Lewis acid (B3) Compound (C): Organoaluminum compound.

<Compound (A): Metallocene> The compound (A) is usually called metallocene, and is a π-electron conjugated ligand, ie, η-cyclopentadienyl structure, η-benzene structure, η-cycloheptatri. It is a transition metal complex in which at least one ligand having an enyl structure or an η-cyclooctatetraenyl structure is coordinated with a transition metal.

Any metallocene can be used in the present invention so long as it can give crystalline polypropylene that can finally be used as a raw material for a molded article having the above-mentioned essential requirements, but a preferable metallocene is represented by the general formula Q- (C ₅ H _4-m
R ¹ _m )-(C ₅ H _4-n R ² _n ) -MXY transition metal compound [wherein (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n ) represents a substituted cyclopentadienyl group, m and n are 1 to 3
And R ¹ and R ² may be the same or different and each is a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group or two carbon atoms on the cyclopentadienyl ring. Represents a hydrocarbon group which is bonded to form one or more hydrocarbon rings which may be substituted by hydrocarbon, Q
Is a divalent group capable of cross-linking (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n ) and is a hydrocarbon group, an unsubstituted silylene group or a hydrocarbon-substituted group. Is a silylene group, M represents one or more transition metals selected from the group consisting of hafnium, zirconium and titanium, X and Y may be the same or different, each of which is a hydrogen, halogen or hydrocarbon group. Indicate one or more kinds selected].

More preferably as the compound (A) of the catalyst,
In the above general formula, R ¹ and R ² may be the same or different, each is an alkyl group having 1 to 20 carbon atoms, Q is a dialkylsilylene group, and M is a hafnium or zirconium transition metal. X and Y may be the same or different, and each is a coordination complex in which one or more kinds selected from a halogen and a hydrocarbon group are in a chiral positional relationship with the central transition metal compound.

However, as will be described later, even if the content of the chiral coordination complex is not 100%, it is sufficiently useful as a polymerization catalyst. On the contrary, in the preparation of the coordination complex, since a non-chiral coordination complex is necessarily produced as a by-product, it is important that the content ratio of the chiral coordination complex is a predetermined value or more.

Preferably, in the above general formula of metallocene, R ¹ and R ² are alkyl groups having 1 to 12 carbon atoms and may be the same or different from each other, Q is a dialkylsilylene group, and M is A transition metal selected from zirconium and hafnium is shown, and X and Y are one or more selected from halogen and a hydrocarbon group and may be the same or different from each other. Among the coordination complexes with transition metals, chiral isomers. It is a metallocene having a content of 80% by weight or more.

More preferably, in the above general formula of metallocene, R ¹ and R ² have a cyclopentadienyl group as a basic structure, and a substituted alkyl group having 1 to 4 carbon atoms, a substituted phenyl group and a substituted naphthyl group. And at least one cyclopentadienyl group selected from an indenyl group, a hydroindenyl group and a fluorenyl group, wherein Q is a dialkylsilylene group containing an alkyl group having 1 to 4 carbon atoms, M is hafnium or purity 90% by weight or more of hafnium, X and Y are one or more kinds selected from chlorine and an alkyl group having 1 to 4 carbon atoms and may be the same or different from each other, and a metallocene having a chiral content of 90% by weight or more. Is.

Examples of such metallocenes are classified as follows according to metals contained: ◆ Hafnium type: dimethylsilylene (3-t-butylcyclopentadienyl) -hafconium dichloride- (fluorenyl), rac- Ethylene bis (indenyl) -hafnium dimethyl, rac-ethylene bis (indenyl) -hafnium dichloride, rac-dimethyl silylene bis (indenyl) -hafnium dimethyl, rac-dimethyl silylene bis (indenyl) -hafnium dichloride, rac-ethylene bis (tetrahydro) Indenyl) -hafnium dimethyl, rac-ethylene-bis (tetrahydroindenyl)-
Hafnium dichloride, rac-dimethylsilylenebis (tetrahydroindenyl) -hafnium dimethyl, rac
-Dimethylsilylenebis (tetrahydroindenyl) -hafnium dichloride, rac-dimethylsilylenebis (2-
Methyl-4,5,6,7-tetrahydroindenyl) -hafnium dichloride, rac-dimethylsilylene bis (2-methyl-
4,5,6,7-Tetrahydroindenyl) -hafnium dimethyl, rac-dimethylsilylenebis (2-methyl-4-phenylindenyl) -hafnium dichloride, rac-dimethylsilylenebis (2-methyl-4-phenylindene) Nyl) -hafnium dimethyl, rac-dimethylsilylene bis (2-methyl
-4-naphthylindenyl) -hafnium dichloride, ra
c-Dimethylsilylene bis (2-methyl-4-naphthylindenyl) -hafnium dimethyl, dimethylsilylene (2,4-
Dimethylcyclopentadienyl) -hafnium dichloride- (3 ', 5'-dimethylcyclopentadienyl), dimethylsilylene (2,4-dimethylcyclopentadienyl)-
Hafnium dimethyl- (3 ', 5'-dimethylcyclopentadienyl), dimethylsilylene (2,3,5-trimethylcyclopentadienyl) -hafnium dichloride- (2', 4 ', 5'
-Trimethylcyclopentadienyl), dimethylsilylene (2,3,5-trimethylcyclopentadienyl) -hafnium dimethyl- (2 ', 4', 5'-trimethylcyclopentadienyl); zirconium-based: dimethylsilylene (3-t-Butylcyclopentadienyl) -zirconium dichloride- (fluorenyl), rac-ethylenebis (2-methyl-4,5,6,7-tetrahydroindenyl) -zirconium dichloride, r
ac-Dimethylsilylene bis (2-methyl-4-phenylindenyl) -zirconium dichloride, rac-Dimethylsilylene bis (2-methyl-4-naphthylindenyl) -zirconium dichloride, dimethylsilylene (2,4-dimethylcyclopenta) Dienyl) -Zirconium dichloride-
(3 ', 5'-dimethylcyclopentadienyl), dimethylsilylene (2,4-dimethylcyclopentadienyl) -zirconium dimethyl- (3', 5'-dimethylcyclopentadienyl), dimethylsilylene (2, 3,5-Trimethylcyclopentadienyl) -zircophenium dichloride- (2 ', 4', 5 '
-Trimethylcyclopentadienyl), dimethylsilylene (2,3,5-trimethylcyclopentadienyl) -zircophnium dimethyl- (2 ', 4', 5'-trimethylcyclopentadienyl), etc .; ◆ Titanium-based: Dimethylsilylene (2,4-dimethylcyclopentadienyl) -titanium dichloride- (3 ', 5'-dimethylcyclopentadienyl) and dimethylsilylene (2,4
Examples include systems such as 3,5-trimethylcyclopentadienyl) -titanium dichloride- (2 ', 4', 5'-trimethylcyclopentadienyl).

<Examples of Suitable Metallocenes> Among the metallocenes listed above, the preferred ones are as follows: dimethylsilylene (2,4-dimethylcyclopentadienyl) -hafnium dichloride- (3 ', 5'- Dimethylcyclopentadienyl), dimethylsilylene (2,4-dimethylcyclopentadienyl) -hafnium dimethyl- (3 ', 5'-dimethylcyclopentadienyl), dimethylsilylene (2,3,5-trimethylcyclopenta) Dienyl) -hafnium dichloride- (2 ', 4', 5'-trimethylcyclopentadienyl), dimethylsilylene (2,3,5-trimethylcyclopentadienyl) -hafnium dimethyl- (2 ', 4', 5'-trimethylcyclopentadienyl) and the like.

Dimethylsilylene (2,4-dimethylcyclopentadienyl) -zirconium dichloride- (3 ', 5'-dimethylcyclopentadienyl), dimethylsilylene (2,4
4-Dimethylcyclopentadienyl) -zirconium dimethyl- (3 ', 5'-dimethylcyclopentadienyl), dimethylsilylene (2,3,5-trimethylcyclopentadienyl) -zirconium dichloride- (2', 4 ', 5'-Trimethylcyclopentadienyl), dimethylsilylene (2,3,5-
Trimethylcyclopentadienyl) -zirconium dimethyl- (2 ', 4', 5'-trimethylcyclopentadienyl) and the like.

Among the above-mentioned preferable metallocenes, zirconocene and hafnocene are more preferable, and a more preferable metallocene is hafnocene having a hafnium compound as a transition metal. Hafnocene is excellent as a transition metal component of the catalyst used in the polymerization method of the present invention in that it can serve as a catalyst for producing crystalline polyolefin having a much higher molecular weight than zirconocene, for example, crystalline polypropylene.

Among the above metallocenes, a meso metallocene having a non-chiral structure may be by-produced during the synthesis of a chiral metallocene, but it is not necessary that all of them be chiral metallocenes in actual use. The meso form is less than a predetermined amount, usually 20 mol% or less, preferably 10 mol%
The following (all metallocene standards) may coexist. However, when using a coexisting substance of meso form,
In some cases, it may be necessary to remove atactic polypropylene produced from the meso form by a known method such as solvent extraction so that the finally obtained polypropylene film satisfies the above-mentioned essential requirements. Whether it can be removed or not depends on the mixing amount of the meso compound and the propylene polymerization activity of the catalyst. The hafnium composing hafnocene in the production method of the present invention is not limited to the one having a purity of 100%, and any one having a purity of 80% or more can be used, and a catalyst having a purity of 90% or more preferably has higher catalytic performance. Demonstrate.

<Catalyst component with carrier> Further, these transition metal compounds (A) are used as a catalyst by themselves in combination with the compound (B) and, if necessary, further combined with the compound (C). It is also possible, but it is also possible to use it in the form of being supported on a fine particle carrier. Such a particulate carrier is an inorganic compound or an organic compound,
The average particle size is 5 to 300 μm, preferably 10 to 20
Those which are 0 μm granular or spherical solids are usually used. The specific surface area (by the BET method) of this fine particle carrier is 10 to 1000 m ² / g, preferably 50 to 700 m ²
Select / g.

Among these, as the inorganic compound used as the carrier, a single substance such as SiO ₂ , Al ₂ O ₃ , MgO, TiO ₂ and ZnO, or a combination of two or more thereof, such as Si, is used.
_{O 2 -Al 2 O 3, SiO} 2 -MgO, SiO 2 -TiO 2, SiO
_2- Al ₂ O ₃ -MgO and the like can be mentioned. Among these,
Those containing SiO ₂ or Al ₂ O ₃ as a main component are preferable.

As the organic compound used as the carrier, α-olefin polymers or copolymers such as ethylene, propylene, 1-butene, 4-methyl-1-pentene and the like having 2 to 12 carbon atoms are used. -Olefin resins, as well as polymers or copolymers of styrene or styrene derivatives can be mentioned.

When the compound (A) constituting the above catalyst is used in a supported form, SiO ₂ or Al ₂ O ₃ or an olefin (co) polymer is used as a preferable carrier, and the compound (A) is formed on the surface of the carrier. A) is the carrying amount 5 × 10 ^{-7 to} 5 × 10 ^-3 mm
ol / g (carrier), preferably 5 × 10 ^{−6 to} 5 × 10 ⁻⁴ mmol / g
It suffices if it is supported on the (carrier).

A metallocene (A) containing a transition metal compound as a main component as a catalyst component used in the production of crystalline polypropylene suitable for the material of the polypropylene molded article of the present invention.
The compound (B) combined with is aluminoxane (B
1), one or more compounds selected from ionic compounds (B2) and Lewis acids (B3) which react with the transition metal compound (A) to form an ionic complex.

Among them, the aluminoxane (B1) is an organoaluminum compound represented by the following general formula [1] or [2].

[0039]

Embedded image

[0040]

Embedded image

[Wherein R ³ is a hydrocarbon group having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, specifically, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group,
Isobutyl group, pentyl group, hexyl group, etc., alkenyl group such as allyl group, 2-methylallyl group, propenyl group, isopropenyl group, 2-methyl-1-propenyl group,
Examples thereof include butenyl group, cycloalkyl group such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group and aryl group such as phenyl group, tolyl group and xylyl group. Of these, an alkyl group is particularly preferable, and each R ³ may be the same or different.

Further, p is a number of 4 to 30, preferably 6 to 30, and more preferably 8 to 30]. The above aluminoxane (B1) can be prepared under various known conditions, and the following method can be specifically exemplified. B11: A method of reacting trialkylaluminum directly with water in an organic solvent which is non-reactive with an organometallic compound, for example, toluene or ether. B12: A method in which a trialkylaluminum is reacted with a salt hydrate (a salt having water of crystallization), for example, copper sulfate hydrate or aluminum sulfate hydrate. B13: a method of reacting trialkylaluminum with water impregnated in silica gel or the like. B14: A method in which trimethylaluminum and triisobutylaluminum are mixed, and this is directly reacted with water in an organic solvent which is non-reactive with an organometallic compound, for example, toluene or ether. B15: A method in which trimethylaluminum and triisobutylaluminum are mixed and reacted with a salt hydrate (a salt having water of crystallization) such as copper sulfate hydrate or aluminum sulfate hydrate. B16: A method in which a product obtained by impregnating water with silica gel or the like is reacted with triisobutylaluminum and then further reacted with trimethylaluminum.

Further, an ionic compound (B2) (hereinafter sometimes referred to as "compound (B2)") which reacts with the transition metal compound (A) to form an ionic complex, and a Lewis acid
Examples of (B3) include JP-A 1-501950, JP-A 1-502036, JP-A-3-179005, JP-A-3-179006, and JP-A 3-20.
Examples thereof include ionic compounds and Lewis acids described in JP-A-7703 and JP-A-3-207704.

Ionic compound (B2) usable in the present invention
Is a salt of a cationic compound and an anionic compound. The anion has a function of cationizing the transition metal compound (A) as a result of reacting with the transition metal compound (A) and stabilizing the transition metal cation species by forming an ion pair. As anion of that kind,
Examples thereof include organic boron compound anions and organic aluminum compound anions.

The above cations include metal cations,
Examples thereof include organic metal cations, carbonium cations, tripium cations, oxonium cations, sulfonium cations, phosphonium cations and ammonium cations.

Of these, an ionic compound containing a boron atom as an anion is preferable, and specifically, triethylammonium tetrakis (pentafluorophenyl) borate and trikis (pentafluorophenyl) borate triethylammonium are used.
-n-butylammonium, triphenylammonium tetrakis (pentafluorophenyl) borate, methylanilinium tetrakis (pentafluorophenyl) borate, dimethylaninium tetrakis (pentafluorophenyl) borate, trimethylanilium tetrakis (pentafluorophenyl) borate, etc. Can be mentioned.

The Lewis acid (B3) is preferably a boron atom-containing Lewis acid, and compounds represented by the following general formula can be used. BR ⁴ R ⁵ R ⁶ (in the formula, R ⁴ , R ⁵ and R ⁶ each independently represent a phenyl group or a fluorine atom which may have a substituent such as a fluorine atom, a methyl group and a trifluorophenyl group).

Specific examples of the compound represented by the above general formula include tri-n-butylboron, triphenylboron, tris [3,5-bis (trifluoromethyl) phenyl] boron,
Examples include tris [(4-fluoromethyl) phenyl] boron, tris (3,5-difluorophenyl) boron, tris (2,4,6-trifluorophenyl) boron, and tris (pentafluorophenyl) boron. Of these, tris (pentafluorophenyl) boron is preferable.

Here, the transition metal compound (A) and the compound (B)
The ratio of used with is aluminoxane (B1) as compound (B)
In the case of using, 1 mol (1 gatom) of the transition metal atom in the transition metal compound (A) is replaced by Al in the aluminoxane (B1).
1 mol (gatom) to 5 × 10 ⁴ mol, preferably 10 mol
˜3 × 10 ⁴ mol, more preferably 50 mol˜2 × 10 ⁴ mo
l range.

When the compound (B2) or the Lewis acid (B3) is used as the compound (B), the transition metal compound (A)
The compound (B2) or the Lewis acid (B3) is added in an amount of 0.01 to 2 × 10 ³ mol, preferably 0.1 to 1 mol, of the transition metal atom therein.
Use in the range of 500 mol is sufficient for most purposes.

The above-mentioned compounds (B) are not limited to one kind alone, and it is possible to use two or more kinds in combination. Further, as the compound (C), that is, the organoaluminum compound, which is optionally used in combination with the polymerization catalyst used in the polymerization method of the present invention, compounds represented by the following general formula can be used.

[0052] ^{_{AlR 7 t R 8 t 'X}} 3- (t + t') ( wherein, R ⁷ and R ⁸ are each an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group or a hydrocarbon group, an aryl group Or, an alkoxy group independently of each other is a phenyl group or a fluorine atom which may have a substituent such as a fluorine atom, a methyl group and a trifluorophenyl group, provided that R is
^At least one of ⁷ and R ⁸ is an organic group. X represents a halogen atom, and t and t'represent any number satisfying the relationship of 0 <t + t'≤3). Specific examples of the organoaluminium compound represented by the above general formula include trialkylaluminium, for example, trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, tri-n-butylaluminum, and the like, dialkylaluminium. Halides such as dimethyl aluminum chloride, dimethyl aluminum bromide, diethyl aluminum chloride,
Alkyl aluminum sesquihalides such as diisopropyl aluminum chloride and the like, for example, methylaluminium sesquichloride, ethyl aluminum sesquichloride, ethyl aluminum sesquibromide, isopropyl aluminum sesquichloride and the like can be mentioned, and not limited to one kind thereof, but two or more kinds thereof are used in combination. It is also possible.

Here, the amount of the organoaluminum compound used as the compound (C) is 1 mol of the transition metal atom in the transition metal compound (A).
Al atom in (C) is 0 to 10 ⁴ mol, preferably 0.02 to
The range is 5 × 10 ³ mol, and more preferably 1 to 3 × 10 ³ mol.

Compound (A), compound thus combined
By using a specific catalyst comprising (B) and a compound (C) optionally combined, propylene is homopolymerized or copolymerized with propylene and an α-olefin other than propylene having 2 to 12 carbon atoms. The crystalline polypropylene used for the polypropylene molded article of the invention is obtained.

As the (co) polymerization method used therefor, a known propylene polymerization process can be used. For example, butane, pentane, hexane, heptane, aliphatic hydrocarbons such as isooctane, cyclopentane and cyclohexane can be used in an inert solvent. , Alicyclic hydrocarbons such as methylcyclohexane, toluene, xylene, aromatic hydrocarbons such as ethylbenzene, and further, among gasoline fractions and hydrogenated diesel oil fractions, the polymerization method is a slurry polymerization method,
Bulk polymerization using propylene itself as a solvent (monomer solvent polymerization), a gas phase polymerization method of carrying out (co) polymerization in a gas phase, and the like can be used.

Propylene or propylene and 2 to 1 carbon atoms
In the polymerization with α-olefin other than propylene of 2, the above-mentioned specific catalyst is a mixture of the compound (A), the compound (B) and the compound (C) which can be optionally combined in advance in an inert solvent. May be supplied to the polymerization reaction system, or the compound (A), the compound (B) and the compound (C) may be separately supplied to the polymerization reaction system. Furthermore, α excluding propylene or propylene and propylene having 2 to 12 carbon atoms
-Polymerization by contacting a small amount of α-olefin in an inert solvent with a catalyst consisting of compound (A), compound (B) and optionally compound (C) prior to the actual polymerization with olefin. By this, propylene or propylene and a carbon number of 2 to 12 are obtained as a preactivated catalyst.
It is also within the scope of the present invention to carry out a production polymerization with an α-olefin other than propylene. Its significance lies in the effect that crystalline polypropylene can be obtained in a good particle shape. In addition, the above-mentioned pre-activation is specifically
From 1 g of α-olefin to 1 mol of the transition metal in (A)
This can be achieved by polymerizing about 10 kg.

As the α-olefin which can be used for the pre-activation, an α-olefin having 2 to 12 carbon atoms is preferably used, and specifically, ethylene, propylene, 1-butene, 1-pentene, 1- Hexene, 4-methyl-1-pentene, 1-octene, 1-decene and the like can be mentioned, with ethylene, propylene and 4-methyl-1-pentene being particularly preferred.

Thus, the prepared specific catalyst used in the present invention or the pre-activated specific catalyst is propylene or propylene and C 2 and C 2 in the above-mentioned polymerization method.
It is used for the polymerization with .alpha.-olefins other than propylene of .about.12, and the polymerization conditions in the propylene polymerization are the same as those in the propylene polymerization using a known Ziegler catalyst.

That is, the polymerization temperature is -50 to + 150 ° C,
Preferably, at a temperature of −10 to + 100 ° C., the polymerization pressure is atmospheric pressure to 7 MPa, preferably 0.2 MPa to 5 MPa, and propylene or propylene and α-olefin excluding propylene having 2 to 12 carbon atoms are placed in a polymerization vessel. To 1m
A (co) polymerization reaction is carried out for about 20 to 20 hours.

It is possible to add an appropriate amount of hydrogen for controlling the molecular weight during the (co) polymerization as in the known propylene polymerization method. After the completion of the (co) polymerization of propylene or propylene and an α-olefin other than propylene having 2 to 12 carbon atoms, a known catalyst deactivation step, a catalyst residue removal step, a drying step, etc. are performed. After going through the treatment steps, the crystalline polypropylene according to the invention is obtained.

The crystalline polypropylene used in the present invention thus obtained may optionally contain an antioxidant, an ultraviolet absorber, an antistatic agent, a nucleating agent, a lubricant, a flame retardant, an antiblocking agent, a coloring agent, Various additives such as inorganic or organic fillers, and further various synthetic resins are blended and usually melt-kneader is used at 190 to 350 ° C. for 20 sec to 3
It is melt-kneaded by heating for about 0 min and, if necessary, extruded into a strand shape, and then further cut and provided as a polypropylene molding material in the form of pellets.

The polypropylene molded article of the present invention is usually
What is called a "mold", and in most cases, the crystalline polypropylene obtained by the above-mentioned specific polymerization method is used as a raw material resin, the known mold molding method as described above, and if necessary, Injection molding method, extrusion molding method (usually hollow molding method;
Also known as "blow molding method"), vacuum molding method, pressure molding method, or a combination molding method of two or more thereof, or the like, and is obtained by molding or further shaping the above material resin. A particularly suitable molding means is an injection molding method. Needless to say, the injection molding method here is not limited to a simple injection molding method, but includes an injection blow molding method (injection blow molding method). The crystalline polypropylene obtained by the production method of the present invention is suitable as a raw material resin for this injection blow molding method.

[0063]

As is apparent from the examples described below, the polypropylene molded article of the present invention exhibits higher heat resistance (HDT: heat distortion temperature) than expected from the melting point. In this respect, the polypropylene molded article of the present invention produced by the polymerization method of the present invention has a unique performance (balance between properties) which is not recognized in the molded article produced from the polypropylene obtained by the conventional polymerization method.
The peculiar performance enables the polypropylene molded product of the present invention to enter the field of application where it was difficult to advance due to the performance limit of the conventional product.

[0064]

EXAMPLES Next, the present invention will be specifically described with reference to examples. The definitions of terms used in Examples and Comparative Examples and the measuring methods are as follows. (1) MFR (unit: g / 10min): JIS K7210 Table 1
Melt flow index (melt flow rate) of the resin according to the condition 14 of. (2) α-olefin component content other than propylene in crystalline polypropylene: Unit: mol%): Measurement item: ¹³ C nuclear magnetic resonance spectrum Measurement target: o-at a polymer concentration of 20% by weight as a sample solution
Dichlorobenzene / deutero (hydrogenated) bromobenzene = 8 /
2 weight ratio mixed solution Measuring device: JEOL-GX270NMR (manufactured by JEOL Ltd.) Measuring conditions: 67.20 MHz, 130 ° C Result processing: Calculated based on the above-mentioned measuring results. (3) Melting point (Tm; ° C): Measured by the method described later Measuring device: DSC7 differential scanning calorimeter (Perkin
Elmer Co., Ltd.) Measurement conditions: Sample polypropylene film piece was heated from room temperature to 230 ° C. at a temperature rising condition of 30 ° C./min, and at the same temperature, 1
After holding for 0 min, lower the temperature at a cooling rate of 20 ° C / min to -20
After reaching the temperature of 10 ° C and holding at the same temperature for 10 minutes, the temperature rising condition 20
The melting point is defined as the temperature at which the endothermic peak showing the maximum endothermic amount when the sample is melted is heated by heating at ℃ / min. (4) Young's modulus (YM; MPa): Measured by the following method: The tensile strengths of MD (longitudinal direction) and TD (horizontal direction) of the sample film were measured according to ASTM D882, whichever was lower. The value of is positioned as the Young's modulus of the film.

[0065]

Example 1 (1.1) Production of Crystalline Polypropylene A stainless steel polymerization vessel equipped with an inclined blade and having an internal volume of 100 dm ³ and equipped with a stirrer was replaced with nitrogen gas, and then n- was placed in the polymerization vessel.
Hexane 50 dm ^3, a toluene solution of methylaluminoxane [Concentration: 2mol / dm ^3); trade name: MMAO (East AKZO Co.) chiral dimethylsilylene (2, 3 containing Al atom converted 2.0 mol, metallocene, 5-Trimethylcyclopentadienyl) -hafnium dichloride- (2 ',
4 ', 5'-trimethylcyclopentadienyl) 0.09 mmol
And meso dimethylsilylene (2,3,5-trimethylcyclopentadienyl) -hafnium dichloride- (2 ',
3 ', 5'-trimethylcyclopentadienyl) 0.01 mmol
The coexisting substance with was added to the polymerization vessel at 20 ° C. together with 0.5 dm ³ of toluene.

Then, after setting the temperature in the polymerization vessel to 45 ° C., a propylene-ethylene mixed gas (propylene 9
3.9 mol%, 6.0 mol% ethylene and 0.1 mol% hydrogen) are continuously fed into the polymerization vessel (feed rate 8 dm ³ / m).
While maintaining the pressure in the polymerization vessel at 0.4 MPa, copolymerization was carried out for 4 hours.

That is, a part of the mixed gas existing in the gas phase portion in the polymerization vessel was continuously discharged to the outside of the polymerization vessel from a valve separately attached to the gas phase portion in the polymerization vessel. After the completion of the polymerization, unreacted propylene, ethylene and hydrogen were discharged from the inside of the polymerization vessel, 2-propanol 3dm ³ as a deactivator was put into the polymerization vessel, and the catalyst was deactivated by stirring at 30 ° C. for 10 minutes.

[0068] Subsequently an aqueous solution of hydrogen chloride in the polymerization vessel (concentration: 12mol / dm ³⁾ 0.2dm ³ and was 30min treated with additives to 60 ° C. Methanol 8dm ^3. After the completion of the treatment, the stirring was stopped and the aqueous phase portion was discharged and removed from the lower part of the polymerization vessel. Then, the same amount of hydrogen chloride aqueous solution and methanol were added and the same operation was repeated.

Then, an aqueous solution of sodium hydroxide (concentration:
5mol / dm ³⁾ 0.02dm ^3, water 2 dm ^3, and methanol was added to the 2 dm ³ polymerization vessel was 10min stirring treatment at 30 ° C.. After draining remove aqueous portion from the polymerization vessel bottom stop stirring after processing, 3 water 8Dm ³ was added in the addition polymerization reactor
The procedure of discharging the aqueous phase portion after stirring for 10 minutes at 0 ° C. was repeated twice.

Next, the polymer slurry was taken out from the polymerization vessel, filtered and dried to obtain the crystalline propylene-ethylene copolymer used in the present invention (MFR 8.5 g / 10 min, ethylene component content 3.22 mol%). 2. 4 kg was obtained. The catalyst and polymerization conditions are shown in Table 1. (1.2) Production of polypropylene molded article and measurement of property value The crystalline propylene-ethylene copolymer 10 used in the present invention obtained by repeating the method of the above (1.1) 5 times.
0 parts by weight of 0.1% by weight of tris (2,4-di-t-butylphenyl) phosphite as a stabilizer, tetrakis [methylene-3- (3 ', 5'-di-t-butyl-4'] -Hydroxyphenyl)
Propionate] 0.05 parts by weight of methane and 0.08 parts by weight of calcium stearate are mixed in a Henschel mixer (trade name), and the mixture is mixed in a single-screw extruder (screw diameter 40 mm and extrusion temperature 230 ° C.). A copolymer pellet (MFR 8.3 g / 10 min) was obtained using the above.

The pellets thus obtained were charged into an injection molding machine and a JIS type test piece (test piece) was molded at a molten resin temperature of 230 ° C. and a mold temperature of 50 ° C. The test pieces obtained were placed in a room with a relative humidity (RH) of 50% and a room temperature of 23 ° C.
Bending stress of 45.
The deflection temperature (HDT) under 1 MPa (N / mm ² ) was measured. Table 1 shows the prescription and measurement results.

[0072]

Comparative Example 1 (c1.1) Production of Crystalline Polypropylene Instead of the catalyst (metallocene and methylaluminoxane) used in Example 1, a method similar to Example 1 in JP-A-62-104812 was used. A catalyst comprising 0.28 mmol (as Ti) of the obtained magnesium chloride-supporting titanium catalyst component, 80 mmol of triethylaluminum and 8 mmol of diisopropyldimethoxysilane as the third component of the catalyst was placed in a polymerization vessel.

Before supplying the propylene-ethylene mixed gas to the polymerization vessel, 0.5 mol of hydrogen was charged, and then the mixed gas (comprising 93.4 mol% of propylene and 6.6 mol% of ethylene) was added to the polymerization vessel to adjust the pressure inside the polymerization vessel. The polymerizer was fed for 2 hours at a feed rate (feed rate) capable of maintaining 0.69 MPa.

In this example, the same operation as in Example 1 was carried out except that the above conditions were adopted and the unreacted mixed gas was not discharged to the outside of the polymerization vessel, and the polymerization temperature was set to 60 ° C. Propylene-ethylene copolymer (MFR 8.0g / 10m
in, ethylene component content 6.50 mol%) was produced. The catalyst and polymerization conditions are shown in Table 1. (c1.2) Manufacture of polypropylene molded article The crystalline polypropylene obtained in the above (c1.1) was operated under the same formulation and molding conditions as in (1.2) of Example 1 to obtain a test piece. A polypropylene molded article was obtained, and its property value was measured. Table 2 shows the prescription and measurement results.

[0075]

Examples 2 to 4 (2.1 to 4.1) Production of crystalline polypropylene A crystalline polypropylene was prepared in the same manner as in Example 1, except that the mixing ratio of propylene and ethylene was changed variously. Got The catalyst and polymerization conditions are shown in Table 1. (2.2 to 4.2) Production of polypropylene molded article and measurement of property values For the four types of crystalline polypropylene obtained by the method of the above (2.1 to 4.1), the same formulation and the same as in (1.2) of Example 1 and Under the molding conditions, four types of polypropylene molded articles, which were test pieces, were manufactured, and their property values were measured. The formulations and measurement results are shown in Table 1.

[0076]

Example 5 (5.1) Production of polypropylene Instead of the mixed gas (propylene, ethylene and hydrogen) in the paragraph (1.1) of Example 1, a mixed gas (propylene 9
4.8 mol%, ethylene 4.6 mol%, 1-butene 0.5 mol%
And 0.1 mol% of hydrogen) were fed into the polymerization reactor, and the same catalyst and polymerization conditions as in (1.1) of Example 1 were used to obtain a crystalline polypropylene. (5.2) Manufacture of polypropylene molded product and measurement of property value For the crystalline polypropylene obtained by the polymerization method of (5.1) above, a test piece was prepared under the same formulation and molding conditions as in (1.2) of Example 1. A polypropylene molded article was manufactured and its property value was measured. The formulations and measurement results are shown in Table 1.

[0077]

[Comparative Examples 2 and 3] (c2.1 and c3.1) Production of Polypropylene In the same manner as in Comparative Example 1 except that the mixing ratio of propylene and ethylene was changed in two ways in (c1.1). Operating under the same catalyst and polymerization conditions as above, two types of crystalline polypropylene were obtained. The catalyst and polymerization conditions are shown in Table 1. (c2.2 and c3.2) Production of polypropylene molded article and measurement of property values Two types of crystalline polypropylene obtained by the polymerization method of the above (c2.1 and c3.1) are compared with those of Comparative Example 1 ( Two types of polypropylene molded articles, which are test pieces, were manufactured under the same formulation and molding conditions as in Section c1.2), and their property values were measured. Table 2 shows the formulations and the measurement results.

[0078]

[Table 1]

[0079]

[Table 2]

Claims (9)

[Claims] 1. A crystalline polypropylene molded article, comprising:
Α-, excluding propylene with 2 to 12 carbon atoms
Molded from crystalline polypropylene with an olefin content (Cm) of 0 to 15 mol% and the deflection temperature under load of the molded product
Polypropylene characterized in that (HDT; ° C) and the melting point (Tm; ° C) of the molded product satisfy the relation 57 ≤ 1.18 x (Tm)-(HDT) ≤ 69. Molding. 2. The deflection temperature under load (HDT;
C.) and the melting point (Tm; C.) of the molded product satisfy the relation 58 ≦ 1.18 × (Tm) − (HDT) ≦ 68.5 expressed by the following equation. The polypropylene molded article according to 1. 3. The deflection temperature under load (HDT;
C.) and the melting point (Tm; C.) of the molded product satisfy the relation 58.5 ≦ 1.18 × (Tm) − (HDT) ≦ 68. 1 or 2
The polypropylene molded product described in. 4. A method for producing a crystalline polypropylene suitable for a polypropylene molded article, comprising the following compound (A):
And (B) is used to homopolymerize propylene or to copolymerize propylene with an α-olefin other than propylene having a carbon number of 2 to 12 so that the α-olefin component content (Cm) is A crystalline polypropylene having a content of 0 to 15 mol%, and the molded product has a deflection temperature under load (H
DT; ° C) and the melting point (Tm; ° C) of the molded product are represented by the following formula: 57 ≤ 1.18 x (Tm)-(HDT) ≤ 69 Method for producing polypropylene: Compound ( A): a transition metal compound having at least one π-electron conjugated ligand, compound (B): aluminoxane (B1), an ionic compound (B2) that reacts with the transition metal compound (A) to form an ionic complex. ) And one or more compounds selected from Lewis acids (B3). 5. A catalyst, wherein the compound (A) is a transition metal compound having at least one π-electron conjugated ligand and the content of its chiral form is 80 mol% or more (transition metal standard). 4. The method for producing crystalline polypropylene according to item 4. 6. Propylene homopolymerization in the presence of a product formed by combining the compound (A) and the compound (B) as a catalyst with an organoaluminium compound as the compound (C) or the number of carbon atoms excluding propylene. The method for producing crystalline polypropylene according to claim 5 or 6, wherein the α-olefin of 2 to 12 is copolymerized. 7. The compound (A) has the general formula Q- (C ₅ H
_The method according to any one of claims 4 to 6, which is a metallocene represented by _4-m R ¹ _m ) -MXY- (C ₅ H _4-n R ² _n ).
[Wherein (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n ) represent a substituted cyclopentadienyl group, m and n are numbers from 1 to 3, and R ¹ and R ² may be the same or different and each is a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group or a hydrocarbon group bonded to two carbon atoms on the cyclopentadienyl ring. Represents a hydrocarbon group forming one or more hydrocarbon rings which may be substituted with
Is a divalent group capable of cross-linking (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n ) and is a hydrocarbon group, an unsubstituted silylene group or a hydrocarbon-substituted group. Is a silylene group, M represents a transition metal selected from the group consisting of hafnium, zirconium and titanium, X and Y may be the same or different, and each is selected from hydrogen, halogen and hydrocarbon groups. Indicates one or more types]. 8. The production method according to claim 4, wherein the transition metal element forming the metallocene is hafnium or hafnium having a purity of 90% by weight or more. 9. In the compound (A), the general formula Q is a dialkylsilylene group and the alkyl group has 1 to 4 carbon atoms, and (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n ) are each an alkyl group-substituted cyclopentadienyl group,
9. M is hafnium or hafnium having a purity of 90% by weight or more, and X and Y are chlorine, bromine and alkyl groups each having 1 to 4 carbon atoms, which may be the same or different from each other. 5. The method for producing crystalline polypropylene according to any one of 1.